Altman takes reins of Y Combinator as Graham steps back

Paul Graham, co-founder and frontman of Y Combinator, is stepping back from his day-to-day responsibilities at the tech incubator, and entrepreneur Sam Altman is taking over as president, Graham announced today in a blog post.

Altman previously co-founded and was CEO of Loopt, a provider of location-based services for smartphones and a YC alumnus that was acquired by Green Dot Corp in March 2012. He has been a partner at YC for a couple of years.

“Why the change?” Graham wrote in his blog. “Because YC needs to grow, and I’m not the best person to grow it. Sam is what YC needs at this stage in its evolution.”

Since its founding in 2005, Y Combinator has become one of the top seed funders in Silicon Valley. It has funded more than 630 companies, including Airbnb, Dropbox, Reddit, Xobni, Weebly, Omgpop and Loopt, according to its website.